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I recommend adding a small AIR HOLE IN BELLOWS iv just killed the shutter in my PRAKTICA TL3air compression / vacume pushing shutter about and it didnt like it,first shutter would fire one curtain halfway and the other slowly,this problem escilated into.shutter auto fire on wind and mirror LOCKED up apature lever STUCK outafter 4 HOURS 'FIXING' (top , bottom and front box off)shutter and winder JAMMED apature lever works and iv got to RESOLDER a wire on light meter (even tho it was a test spair its a shame as light meter still worked)if anybody has got any tips on the procedure for reassembling said camera that would be ace as i havent figured what was wrong to fix and lever set up on replacing front

Good tutorial, I just want to state for readers that you'll need to use a MEDIUM FORMAT lens. The nature of 35mm lenses makes them unable to focus more than a couple millimeters away from the sensor. Medium format is kinda obsolete though so it shant be hard to find one.

That's what I thought you meant. Why is a medium-format lens necessary? If one designs a tilt-shift lens correctly, it should be marginally sharp from it's closest distance to infinity, no? I see people using them for architecture all the time. My Nikon's FFD is 46.5mm - much more than just 'a couple millimeters'. If it's off by a few millimeters either way, you'll lose the ability to focus to infinity/ focus closely. I know this because I used to have a stupid adapter to use my old Minolta lenses on my Nikon DSLRs. It only allowed me to focus a maximum of about 5 feet away, and no further, although I could have used them as macro lenses, in hindsight.

Are you saying that because of the much larger size of the glass, more of the shot will be in focus, as there is less curvature in the glass in the area the sensor will record?

a 35mm lens will focus and work as a tilt-shift, but only on macro shots, as you need to keep it very close, and sometimes inside the lens body in order to fit the focused section within the film/sensor. a larger format lens (therefore a larger flange distance) helps the focus of the photo to fall inside the camera's range, whether held close to the body (for marco shots) or further away (for landscapes)

that's why nikon f lenses can be used on canon eos using adaptors, but not the other way around

Perhaps I am misunderstanding what you mean by close to the body for macro etc. But the lens needs to be farther from the camera body for macro and closer for landscape. Hence the use of bellows attachments and extension tubes for macro photography. When choosing lenses for this application you are looking at the cone of image the lens projects towards the camera, what is known as coverage. This would be why the medium format lenses might be better, they are made to cover a larger negative size at the given focal length than 35mm lenses.

This is because medium format lenses are a large distance from the film, a few inches, much larger than 35mm cameras. This is why we can stick it on a plunger and toy with it, it was designed to be that far away. A 35mm lens is designed to be 40ish mm from the sensor, and any slight screwing with that makes you lose infinity focus or lose the ability to focus closely.

Shifting the lens away from the body loses infinity focus but increases the close focus capacity, as seen with extension tubes, which simply moves the lens plane further from the sensor plane (or film plane). The focal length of a lens is measured at infinity, it is more complicated in multi-element (the elements shift inside) lenses but in theory the focal distance is the same for a 90mm lens regardless of whether it is on a DX, FX, medium format, 4x5 etc. The angle of view changes as you change format but 90mm focal length is 90mm focal length. The lenses for the different formats are much different for the requirements of covering the film effectively, and tend to get more expensive as you move up in format. An easy place to see this is in large format where the focus adjustment is external to the lens. There focus is managed via the bellows and you can focus closer and closer until you run out of bellows draw. It is also a great place to look at coverage as you can you can change from 8x10 to 4x5 format as easily as swapping the 8x10 back for a 4x5 back and the focus does not change, you can put on a medium format back, and as long as the backs are true, the focus in all will be the same. Going from 4x5 to 8x10 is trickier if you are using a lens designed for 4x5 (cheaper), you can put the 8x10 back on but the corners of the image will probably be dark as the image cone cast by the lens is not large enough to completely cover the film (forget about tilts and shifts), you might even get a circular image on the film, it depends on the lens. The wiki article Sprockette linked said: "Flange focal distance is one of the most important variables in a camera, as lens seating errors of as little as 0.01 mm will manifest themselves critically on the imaging plane and focus will not match the lens marks." It is not saying you cannot focus if your lens mount is off by 0.01 mm, it is saying the calibration of the scale (lens marks) will be off. Important in some places such as movie cameras, but not so much where we focus by eye. I suppose it might mess up autofocus on slrs but by the time you have your lens on a rubber plunger you have pretty much given up on autofocus. This is a long winded way (sorry) of just trying to clarify a simple point that started with my trying to clarify what "Sprockette" actually meant with the statement: "held close to the body (for marco shots) or further away (for landscapes)" which still seems backwards if we are referring to lens distance to the camera body.